// ex8_7_6.cpp
#include <iostream>
double mass(double density, double volume);
double mass(double density);

void repeat(int n, const char* str);
void repeat(const char* str);

template <class T>
T average(T a, T b);

int average(int a, int b);
double average(double x, double y);

char mangle(const char);
char *mangle(const char *str);
